Container and lid with multiple seals therebetween and methods for making and using the same

ABSTRACT

A moisture tight container includes a container body and a lid preferably linked to the body by a hinge. The body and lid include at least a first seal and a second seal in series to provide a moisture tight seal between the body and the lid. The first seal includes mating of thermoplastic-to-thermoplastic sealing surfaces of the body and lid respectively. The second seal includes mating of thermoplastic-to-elastomeric sealing surfaces of the body and lid, respectively, or of the lid and body, respectively.

BACKGROUND OF THE INVENTION 1. Field of Invention

This invention relates generally to containers for products susceptibleto degradation from moisture. More particularly, this invention relatesto flip-top moisture tight containers which are simple to open and closerepeatedly and which include two or more seals in series between the lidand the body which reliably provide moisture tightness after severalcycles of opening and closing. Containers according to the presentinvention may be utilized for, e.g., pharmaceuticals, probiotics,nutraceuticals, diagnostic test strips and other moisture sensitiveitems.

2. Description of Related Art

The efficacy of medication may be compromised by moisture. As themedication absorbs moisture, the medication may become less effectivefor its intended purpose. Diagnostic test strips, such as blood glucosetest strips that are used in diabetic care, can also be adverselyaffected by exposure to moisture.

Medication and/or test strips are typically stored in a container. Sucha container may include a body that defines an interior for housing aproduct, and an opening leading to the interior. A cap or lid may alsobe included, optionally connected to the body by a hinge. By closing thelid on the body to cover and seal the opening, the container is closedand contents may be safely stored therein.

Products such as diagnostic test strips rely on certain environmentalconditions to provide an accurate reading when used. If subjected to acertain moisture or relative humidity, these products can provide falsereadings with hi or low bias. Thus, moisture can significantly reducethe shelf life of these products. Consumers that require diagnostic teststrip testing, such as the diabetic market, often test multiple timeswithin a 24 hour period and depend on the accuracy of the readings theyget.

Medication and diagnostic test strips can encounter moisture at multipletimes in their life cycles. Such an encounter may occur during themanufacturing stage, during shipping, while the product is in storageprior to being sold, while the product is in storage after being sold,and each and every time a container containing the product is opened sothat the product can be used. Even after products are stored in moisturetight containers, there still exists a small amount of moisture ingressthrough the seal, which over time can be deleterious to moisturesensitive contents inside. For this reason, a desiccant material (e.g.,in the form of a desiccant entrained polymer) is typically provided inthe container to absorb moisture. However, the desiccant material addsto the cost of manufacturing. An improved seal would translate to areduced volume of desiccant to achieve the calculated moisture budgetand thus a less expensive-to-manufacture container.

On the other hand, the seal itself should not significantly add to thecost of making the container or else the cost savings through reduceduse of desiccant can be cancelled out. In addition, the seal itself mustbe carefully designed so that it does not require significant force toopen while at the same time not being too easy to open such that thecontainer could inadvertently pop open, e.g., due to pressure changesthat may occur during transport. In the pharmaceutical and diagnosticspackaging business, it is important to balance product improvements withmanufacturing efficiencies and cost realities.

There is thus a need for an improved flip-top container forpharmaceutical or diagnostic test strip use, which is inexpensive tomake and provides a reliably moisture-tight sealing effect after severalcycles of opening and closing, without requiring high opening force toopen.

SUMMARY OF THE INVENTION

Accordingly, a moisture tight container in accordance with an exemplaryembodiment of the present invention is provided. The container has acontainer body having a base and a sidewall extending from the base. Thebody defines an interior configured for housing product, such asdiagnostic test strips, for example. The body further has an openingleading to the interior. A lid is connected to the body by a hinge andis pivotable about the hinge with respect to the container body to movethe container between a closed position in which the lid covers theopening so as to create a moisture tight seal with the body and an openposition in which the opening is exposed. The moisture tight seal isprovided by a plurality of engaged mating seals in series between thebody and the lid when the lid is in the closed position. The pluralityof engaged mating seals includes at least a first seal and a secondseal. The first seal is formed by mating a thermoplastic sealing surfaceof the body to a thermoplastic sealing surface of the lid. The secondseal is formed by mating a thermoplastic sealing surface of the bodywith an elastomeric sealing surface of the lid. The elastomeric sealingsurface includes an elastomeric ring that is configured to be compressedby an upper surface of a rim surrounding the opening when the lid is inthe closed position. Vertical compression of the elastomeric ring causesa portion of the ring to elastically expand radially into a voidprovided between the body and the lid.

A moisture tight container in accordance with another exemplaryembodiment of the present invention thus includes a body and a lid. Thebody defines an interior for housing a product, and an opening leadingto the interior. The lid is connected to the body with a hinge. The lidis movable with respect to the body between a closed position in whichthe lid covers the opening and is mated to the body, and an openedposition in which the opening is exposed. A plurality of seals arelocated between the body and the lid. The seals are in series when thelid is in the closed position. The plurality of seals includes a firstseal that requires an opening force to transition from the closedposition to the opened position, and a second seal in combination withthe first seal not requiring more than the opening force to transitionfrom the closed position to the opened position. The first seal isformed by mating thermoplastic-to-thermoplastic sealing surfaces, andthe first seal includes an undercut of the body relative to a centralaxis of the body. The second seal is formed by matingelastomer-to-thermoplastic sealing surfaces, and theelastomer-to-thermoplastic sealing surfaces includes an elastomer formedin the lid or on the body, optionally with multi-shot injection molding.The thermoplastic is incompressible and the elastomer is compressibleand preferably resilient.

BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS

The invention will be described in conjunction with the followingdrawings in which like reference numerals designate like elements andwherein:

FIG. 1 is a perspective view of a container in accordance with anexemplary embodiment in an opened position.

FIG. 2 is an enlarged cross-sectional view which illustrates a firstvariation of the exemplary embodiment of FIG. 1.

FIG. 3 is an enlarged cross-sectional view which illustrates a secondexemplary embodiment of the exemplary embodiment of FIG. 1.

FIG. 4 is a cross-sectional view which illustrates the features of FIG.2 and further shows additional portions of a container in accordancewith the first variation of the exemplary embodiment of FIG. 1.

FIG. 5 is a cross sectional view which illustrates the features of FIG.3 and further shows additional portions of a container in accordancewith the second variation of the exemplary embodiment of FIG. 1.

FIG. 6 is a perspective view of a container in accordance with a secondexemplary embodiment in a closed position.

FIG. 7 is a perspective view of the container of FIG. 6 in an openedposition.

FIG. 8 is an enlarged cross sectional view taken along section line 8-8of the container of FIG. 7 illustrating sealing surfaces in the lid.

FIG. 9 is an enlarged cross sectional view taken along section line 9-9of the container of FIG. 6 illustrating engagement of first and secondseals in series to create a moisture tight seal.

FIGS. 10A and 10B are schematic illustrations showing the elastomericring of the lid immediately before engagement with the thermoplasticsealing surface of the body (FIG. 10A) followed by sealing engagement ofthe elastomeric ring of the lid with the thermoplastic sealing surfaceof the body (FIG. 10B).

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

Generally, the invention is directed to containers and methods formaking the same for reducing the amount of moisture that enters acontainer between the container body and the lid that seals the body. Inone aspect, the disclosed embodiments are configured to reduce theamount of moisture that can flow between the body and the lid byproviding at least two seals in series, wherein one such seal is formedby an elastomer-to-thermoplastic interface, which uniquely does notincrease force needed to open the container. As used herein, the term“elastomer” is to be understood in its broad sense. A particularlypreferred elastomer is a thermoplastic elastomer (TPE), optionally onehaving a Shore A hardness of from 20 to 50, preferably from 20 to 40,more preferably from 20 to 35. Alternatively, the term “elastomer” mayinclude silicone rubbers or other preferably injection moldable soft andresilient materials appropriate for creating a compression seal againsta harder (e.g., thermoplastic) surface. In any embodiment, the elastomershould be configured for repeated use, i.e., should not degrade overseveral cycles (e.g., at least 10, preferably at least 25, morepreferably at least 50 cycles) of opening and closing.

Optionally, the invention relates to a container produced in amulti-shot injection molding process wherein the elastomeric seal isproduced in one shot and the thermoplastic container is produced inanother shot. Container embodiments as disclosed herein preferablyincorporate a hinged flip-top lid, wherein the body and lid includetherebetween a low mass elastomer-to thermoplastic seal working inseries with a thermoplastic-to-thermoplastic seal between the body andlid. The combined seals further reduce moisture vapor transmission intothe container when closed than either seal alone, allowing for longershelf life protection while still enabling the container to have a lowopening force to benefit consumer use.

The external container is constructed of two materials, namely(primarily) a base thermoplastic (e.g., polypropylene) and an elastomer,preferably a thermoplastic elastomer (TPE) as one sealing surface of theinvention. The container has an integrated lid connected to the body bya hinge, optionally a living hinge, which is designed to be easilyopened and closed by the consumer. By nature of the material selectionand thermoplastic-to-thermoplastic seal design, the container has a lowmoisture vapor transmission rate (MVTR). This container alsoincorporates an elastomer material to create an additionalelastomer-to-thermoplastic seal to further reduce the MVTR. By furtherreducing the MVTR, the container requires less moisture protection viaany method of desiccation to achieve a targeted shelf life. Thecombination of seals allows the container to provide a lower MVTR thanan otherwise comparable reference container having onlythermoplastic-to-thermoplastic sealing, and at the same time allows fora lower opening and closing force than would be expected when using athermoplastic-to-elastomer seal alone. In addition, the low mass ofelastomer material will still allow the recycle/re-use of the externalcontainer material in a container production process.

A thermoplastic hinge flip-top container in accordance with an exemplaryembodiment of the present invention is constructed of materials with alow vapor transmission rate, e.g., polypropylene. In addition, thecontainer lid is designed with a sealing mechanism that incorporatesboth a thermoplastic-to-thermoplastic seal in combination with athermoplastic-to-elastomer seal that is permanently produced optionallyinside the lid seal area, optionally via multi shot injection molding.The thermoplastic-to-thermoplastic seal area may be designed with anundercut at an angle (or rounding or slope) to the center axis of thevial that is not only part of the thermoplastic-to-thermoplastic seal,but due to the geometry, also controls the opening and closing force ofthe vial. By having the thermoplastic-to-thermoplastic seal work inseries with the thermoplastic-to-elastomer seal, the compression forcenecessary to be applied to the thermoplastic seal to achieve the samelevel of moisture ingress may, in an optional aspect of the invention,be reduced. This may facilitate reduction of opening and closing force,thus making the container easier to use for the consumer. This isparticularly useful for consumer populations that may have difficulty inopening and closing containers such as patients with diabeticneuropathy, or senior citizens.

A thermoplastic-to-thermoplastic seal relies on the mating of twoincompressible surfaces that must match geometrically very closely inorder to provide a closing relationship (e.g., snap-fit) and to act asan effective moisture barrier. This requires sufficient compressionforce to mate the opposing incompressible surfaces, thus forming theseal. The effectiveness of the seal is dependent on the area of contactand the amount of air space (e.g., through microgaps or due toimperfections or wear and tear of the thermoplastic material) betweenthe surfaces that allow moisture to pass through.

A thermoplastic-to-elastomer seal relies on one incompressible surface(the thermoplastic surface) mating with a compressible and preferablyresilient surface (the elastomeric surface). This type of seal relies ongenerating sufficient force between the surfaces to compress theelastomer such that it “fills” any possible gaps or imperfections in theopposing incompressible surface. This pressure must be maintained at alltimes when the container is closed to provide moisture tightness andthen overcome in order to open the container.

By combining a thermoplastic-to-thermoplastic seal in series with athermoplastic-to-elastomer seal, the moisture vapor ingress can bereduced while still maintaining the container opening force in a rangethat is ergonomically advantageous to the consumer population.

In one optimal aspect of the embodiments disclosed herein, theelastomer-to-thermoplastic seal is configured and oriented such that thedirection of compression of the seal is parallel with the main axis ofthe vial and vertical to the seal surface. This is the case whether theelastomer is on an inner portion of the vial lid, on an outer rimprojecting radially from the vial body or on a top edge of the vial bodydisposed around the opening (or optionally two or all three of theforegoing). This way when the vial is opened and closed, theelastomer-to-thermoplastic seal is not subject to radial forces that canrub the elastomer and scarf or damage the seal (which may occur if suchseal was on the side of the vial rim or on the inner skirt of the viallid). This enables repeated openings without deteriorating performanceof the elastomer-to-thermoplastic seal. This configuration enables theuse of a lower durometer seal material which requires less compressionforce and again provides lower opening force with lower ingress ratesthan a reference vial that is otherwise identical but for theelastomer-to-thermoplastic seal. In addition, this configuration doesnot increase the opening force of the seal, unlike a stopper-type sealwith a radially compressed elastomeric element.

Referring now in detail to the various figures of the drawings whereinlike reference numerals refer to like parts, there is shown in FIG. 1 acontainer that may be used in combination with various features in orderto provide exemplary embodiments of the present invention. Container 100may be made primarily from one or more injection moldable thermo-plasticmaterials, including, for example, a polyolefin such as polypropylene orpolyethylene. According to an optional embodiment, the container may bemade from a mixture comprising primarily thermo-plastic material and avery small proportion of thermoplastic elastomer material.

Container 100 includes a container body 101 having a base 155 and anoptionally tubular sidewall 105 extending therefrom, the body 101defining an interior 115 configured for housing product, e.g.,diagnostic test strips. The sidewall 105 optionally terminates at a lip110 having a top edge, the lip 110 surrounding an opening 107 of thebody 101, leading to the interior 115.

A lid 120 is preferably connected to the body 101 by a hinge 140,optionally a living hinge, creating a flip-top container 100 or vial.The lid 120 is pivotable about the hinge 140 with respect to thecontainer body 101 to move the container between a closed position (see,e.g., FIG. 4 or 5) in which the lid 120 covers the opening 107(preferably so as to create a moisture tight seal with the body) and anopen position (see, e.g., FIG. 1) in which the opening 107 is exposed.

Container body 101 may optionally include outer rim 145 that projectsradially outward from the sidewall 105 and completely encirclescontainer body 101 near a top thereof. Optionally, the lip 110 projectsvertically from the rim 145. Optionally, in any embodiment, the lip 110has a thickness approximately equal to the remainder of the sidewall105. Optionally, in any embodiment, the lip 110 has a thickness slightlyless than that of the remainder of the sidewall 105.

Lid 101 includes a lid base 119 and preferably a depending skirt 125.Lid 101 further includes a lid outer rim 131 and optionally a thumb tab121 extending radially from the lid 120. In order to close container100, the lid 120 is pivoted about the hinge 140 so that the lid 120covers the opening 107 and engages respective mating sealing surfaces ofthe lid 120 and body 101, to place lid 120 in closed position.

FIG. 2 is a sectional view of a container in accordance with a firstvariation of the exemplary embodiment of FIG. 1. Body 101 is shown nearthe bottom of the figure while lid 120 is shown near the top of thefigure. As discussed above with respect to FIG. 1, the body 101optionally includes outer rim 145 which projects radially about thecircumference of body 101 and near the top of body 101. Lid 120 includeslid outer rim 131, optionally projecting radially from the inner portionof the depending skirt 125 of the lid 120.

When the lid 120 is in the closed position, lid rim surface 208 facesbody rim surface 206. Thus, when lid 120 is in the closed position, bodyrim surface 206 and at least portions of lid rim surface 208 engage eachother. Affixed to body rim surface 206 is elastomer seal 210 a. The seal210 a is preferably an annular ring disposed around the circumference ofbody rim surface 206. In the illustrated exemplary embodiment, anelastomer-to-thermoplastic seal is created by elastomer seal 210 aengaging and being compressed by lid rim surface 208.

Lid 120 includes lid interior 109, defined by lid base 119 and skirt125. The lip 110 of body 101 extends into lid interior 109 when the lid120 is in the closed position. In that position, body undercut surface204 of body 101 mates with lid undercut surface 202. Accordingly, athermoplastic-to-thermoplastic sealing surface is formed. In addition,this configuration provides a closing position, e.g., via a snap-fitmating configuration, to retain the lid 120 in the closed position andprevent it from inadvertently opening. As shown in FIG. 2, thethermoplastic-to-thermoplastic seal and the closing position are formedby respective undercut surfaces 204, 202. This may be defined, forexample, with reference to an axis 400 (see FIG. 4) extending through acenter of body 101 along its length. Lid undercut surface 202 and bodyundercut surface 204 are not parallel to that axis 400. Rather, asshown, lid undercut surface to 202 and body undercut surface 204 areformed at a slight angle, e.g., from 10° to 30° relative to the axis400. Optionally, the respective undercut surfaces may alternatively becomplimentarily rounded or sloped to mate with each other. With any suchundercut configuration, if a user attempts to lift the lid 120 from body101 to transition the lid 120 to an opened position, an opening forcewill be required to overcome the force between lid undercut surface 202and body undercut surface 204 when the lid 120 is in the closedposition.

In the exemplary embodiment shown in FIG. 2, lid 120 is shown asoptionally including lid elastomer seal 212, which is optionally in theform of an annular ring affixed to lid base 119 adjacent to or abuttingskirt 125. Thus, a seal may be formed between lid elastomer seal 212 andtop edge 110. This creates an elastomer-to-thermoplastic seal betweenlid elastomer seal 212 and top edge 110 when the lid 120 is in theclosed position. Optionally, the invention may omit either elastomerseal 212 or elastomer seal 210, thus providing only a singleelastomer-to-thermoplastic seal in an optional embodiment.

It is contemplated that embodiments according to aspects of theinvention may include multiple and different seals in series between lid120 and body 101. For example, the seals may comprise the seal betweenlid undercut surface 202 and body undercut surface 204 and the sealbetween elastomer seal 210 a and lid rim surface 208. Alternatively, thetwo seals may comprise the seal between lid undercut surface 202 andbody undercut surface 204 and the seal between lid elastomer seal 212and top edge 110. While three seals (labeled as Seal A-C) are shown inFIG. 2, this is merely exemplary, as two seals or greater than threeseals may be included in accordance with exemplary embodiments of theinvention. For example, it is possible for there to be a total of threeseals, more than three cells, or only two seals as explained above.Furthermore, at least one of the seals is an elastomer-to-thermoplasticseal and at least one of the seals is a thermoplastic-to-thermoplasticseal. In other words, any two (or more) of the three seals shown may beincluded, as long as a combination of elastomer-to-thermoplastic andthermoplastic-to-thermoplastic is included.

It should further be noted that the thermoplastic-to-thermoplastic sealprovides the compression force needed to maintain theelastomer-to-thermoplastic seal. This configuration does not requirethat the elastomer-to-thermoplastic seal be a source of radialcompressive force (e.g., as is the case with an elastomeric stopperplugged into a tube). As such, the elastomer-to-thermoplastic seal doesnot add to the opening force necessary to overcome thethermoplastic-to-thermoplastic seal to transition the lid 120 from theclosed position to the opened position. In fact, resilience of thecompressed elastomer when the lid 120 is in the closed position mayresult in a slight vertical spring force biasing the respective undercutsurfaces 202,204 vertically against each other, thus reinforcing orstrengthening the thermoplastic-to-thermoplastic seal. Thus, ifanything, such slight vertical spring force created by theelastomer-to-thermoplastic seal may tend to actually reduce the openingforce compared to an otherwise identical container without anelastomeric sealing surface.

As discussed above with respect to the exemplary embodiment shown inFIG. 2, elastomer seal 210 a is affixed to an upper surface of outer rim145 of the body 101. FIG. 3 shows an alternative exemplary embodiment inwhich elastomer seal 210 b is affixed to lid outer rim 131 and is incontact with outer rim 145 of body 101. In this manner, with regard tothe embodiment of FIG. 2 and the embodiment of FIG. 3, anelastomer-to-thermoplastic seal is formed.

FIG. 4 shows the seals which are illustrated in FIG. 2 and furtherillustrates more of body 101 that is shown in FIG. 2. FIG. 4 is helpfulfor illustrating the relationship between the sealing surface that isformed between lid undercut surface 202 and body undercut service 204and central axis 400 which runs along the length of body 101 and throughits center. As can be seen in FIG. 4, lid undercut surface 202 and bodyundercut surface 204 form an undercut because the seal between these twosurfaces is not parallel to central axis 400. In this manner, theundercut between lid undercut surface 202 and body undercut service 204includes compression force vectors in both vertical and horizontaldirections. The vertical compression force vector requires that anopening force be applied in order to separate lid 120 from body 101 andthus transition the lid 120 from the closed position to the openedposition.

FIG. 5 shows the seals which are illustrated in FIG. 3 and furtherillustrates more of body 101 that is shown in FIG. 3. FIG. 5 is alsohelpful for illustrating the relationship between the sealing surfacethat is formed between lid undercut surface 202 and body undercutsurface 204 and central axis 400 which runs along the length of body 101and through its center. The configuration and function of respectiveundercut surfaces 202,204 of lid 120 and body 101 are identical to thoseshown in FIG. 4 and are not rehashed here for the sake of brevity.

The combination of a thermoplastic-to-thermoplastic seal in series withan elastomer-to-thermoplastic seal according to an optional aspect ofthe invention provides an MVTR through the sealing system of a maximumof optionally 42 μg/day-cm of seal circumference/day when the ambientconditions are a minimum of 30° C./80% relative humidity (RH) externallyand a maximum of 30° C./1% RH internally, while allowing for an openingforce of optionally no greater than 3 N/cm of seal circumference.

Referring now to FIGS. 6-10B, there is shown a second exemplaryembodiment of a container 300 according to an optional aspect of theinvention. Many features of the container 300 of FIGS. 6-10B are similaror identical to corresponding features of the container 100 of FIGS.1-5. Therefore, only a general summary is provided here of such similaror identical corresponding features as with the previously describedembodiments. However, key differences as between the embodiments andadditional embellishments are noted.

Container 300 includes a body 301 having a base 355 and optionally asidewall 305 extending from the base. The body 301 defines an interior315. The sidewall 305 optionally terminates at a lip 310 having a topedge 311. The lip 310 surrounds an opening 307 of the body 301, leadingto the interior 315. In the embodiment shown, container body 301includes outer rim 345. The lip 310 optionally projects vertically fromthe rim 345.

A lid 320 is preferably connected to the body 301 by a hinge 340,optionally a living hinge, creating a flip-top container 300 or vial.The lid 320 is pivotable about the hinge 340 with respect to thecontainer body 301 to move the container 300 between a closed positionand an open position. In the embodiment shown, lid 301 includes lid base319 and preferably a depending skirt 325 and thumb tab 321.

When the lid 320 is in the closed position, a moisture tight seal 460 isformed by a plurality of engaged mating seals in series, including atleast a first seal 462 and a second seal 464. The first seal 462 isformed by mating a thermoplastic sealing surface of the body 301 with athermoplastic sealing surface of the lid 320. The first seal 462 isconfigured to require an opening force to disengage. In the optionalembodiment shown, the first seal 462 comprises the engagement ofundercut surface 404 of body 301 with undercut surface 402 of lid 320.This seal is identical to the undercut-to-undercut seal disclosed abovewith respect to the container 100 of FIGS. 1-5 and will thus not beelaborated upon further here.

The second seal 464 is formed by mating a thermoplastic sealing surfaceof the body 301 or lid 320 with an elastomeric sealing surface of thebody 301 or lid 320. In the optional embodiment shown, the second seal464 is formed by mating a thermoplastic sealing surface of the body 301with an elastomeric sealing surface of the lid 320. The elastomericsealing surface 430 comprises an elastomeric ring 432 configured to becompressed by a thermoplastic upper surface 311 of a lip 310 surroundingthe opening 307 when the lid 320 is in the closed position. As bestshown in FIGS. 9-10B, vertical compression of the elastomeric ring 432causes a portion of the ring 432 to elastically expand radially into avoid 480 provided between the body 301 and the lid 320. This operationis now explained in detail.

The term “ring” as used herein can refer to an annular round elementwith a central opening. However, a “ring” is not necessarily limited tosuch configuration and could include non-round configurations as well aselastomeric elements that are filled in, at least in part, in the center(i.e., where an opening of a ring may otherwise be). As such, a “ring”could include a disc-shaped elastomeric member, for example.

FIG. 9 shows a partial enlarged cross section of the container 300 withthe lid 320 in the closed position. As shown, the first seal 462 isprovided, comprising the engagement of undercut surface 404 of body 301with undercut surface 402 of lid 320. The second seal 464 comprisesengagement of the thermoplastic upper surface 311 of the lip 310 with anengagement surface 430 of the elastomeric ring 432 provided on theunderside of the base 319 of the lid 320. As can be seen in FIG. 9, acompression seal provided between the upper surface 311 of the lip 310and the elastomeric ring 432 causes the cross section of the ring 432 toappear slightly stepped or indented along the engagement surface 430 ofthe elastomeric ring 432. This indent is more pronounced in the enlargedview shown in FIG. 10B. FIG. 10A shows the cross section of the ring 432immediately before it contacts the upper surface 311 of the lip 310 toform the second seal. As shown in 10A, the ring 432, when not engagedwith the lip, does not have such an indent. The indent in the engagementsurface 430 of the elastomeric ring 432 is the product of elastomericdeformation of the ring 432 resulting from sealing engagement with therim 310.

Notably, the elastomeric ring 432 is not bounded or blocked on either animmediate right side 432 _(R) or left side 432 _(L) thereof. As such,when the elastomeric ring 432 is compressed vertically, a portionthereof elastically expands or migrates radially outward, inward orboth. A void 480 is provided, e.g., between the elastomeric ring 432 andthe skirt 325 of the lid 320 to provide “living space” for the ringmaterial to radially expand when the second seal 464 is engaged. FIG.10B illustrates the radially expanded portion 432 _(E) of theelastomeric ring 432 (shown expanded in direction E of FIG. 10B),occupying a portion of the void 480. To the extent such expansionappears in the Figures to be exaggerated compared to actualimplementation, it is merely for illustrative purposes. This radialexpansion into the void feature provides at least two importantfunctions.

First, it results in tempering the vertical spring force between theelastomer and the rim. While it is desired that some slight spring forceis provided to strengthen or reinforce the first seal, excessive springforce may tend to reduce the opening force to an extent that thecontainer may inadvertently pop open. A balance must be struck between adesirably low opening force on the one hand (especially for elderlyand/or diabetic users) and an opening force that is so low that it canresult in inadvertent container openings, e.g., via common pressurevariations that may occur within the container during transport. Whenthe elastomer is permitted to expand radially, the vertical spring forcemay thus be provided at an acceptable level.

The second important function is that the surface area of contactbetween the sealing surfaces of the second seal increases via radialexpansion of the ring's elastomeric material. This increase of theelastomer-to-thermoplastic sealing surface area provides a tighter sealat the site of engagement of the second seal.

It should be understood that any of the seal configurations disclosed inFIGS. 1-5 may be combined with those disclosed in FIGS. 6-10B.

Ingress Performance for the seal alone is measured by taking the totalvial ingress rate and subtracting out the MVTR (moisture vaportransmission rate) through the thermoplastic comprising the outer shellof the vial.

In an exemplary embodiment, when the lid is in the closed position, themoisture vapor transmission rate MVTR is less than 370 μg/day at 30°C./80% RH (relative humidity). In an exemplary embodiment of a 24 mlvial according to embodiments of the invention, the weight of adesiccant entrained three phase polymer sleeve is 2.5-3.25 grams(optionally about 3.0 g) and the moisture ingress is about 400micrograms per day at 30° C./70% RH. In an exemplary embodiment of a 17ml vial according to embodiments of the invention, the weight of adesiccant entrained three phase polymer sleeve is 2.0-2.75 grams(optionally about 2.5 g) and the moisture ingress is about 300micrograms per day at 30° C./70% RH. The term “three phase polymer”refers to a desiccant entrained polymer comprising a base polymer,desiccant and channeling agent, e.g., as described in U.S. Pat. Nos.5,911,937, 6,080,350, 6,124,006, 6,130,263, 6,194,079, 6,214,255,6,486,231, 7,005,459, and U.S. Pat. Pub. No. 2016/0039955, each of whichis incorporated herein by reference as if fully set forth.Advantageously, in an optional aspect of the invention, the second sealpermits reduced use of such desiccant material, resulting in lowermanufacturing costs.

Broadly speaking, the term “moisture-tight” is defined as having amoisture ingress (after three days) of less than 1500 μg of water, inanother embodiment, less than 500 μg of water, in a further embodiment,less than 300 μg of water, in yet another embodiment, less than 150 μgof water, as determined by the following test method: (a) place one gramplus or minus 0.25 grams of molecular sieve in the container and recordthe weight; (b) fully close the container; (c) place the closedcontainer in an environmental chamber at conditions of 80% relativehumidity and 72° F.; (d) after one day, weigh the container containingthe molecular sieve; (e) after four days, weigh the container containingthe molecular sieve; and (f) subtract the first day sample from thefourth day sample to calculate the moisture ingress of the container inunits of micrograms of water.

In an exemplary embodiment, when the first seal and the second sealcombined provide the container when the lid is in the closed position alower MVTR than the first seal would provide without the second seal.

In an exemplary embodiment, when the first seal and the second sealcombined provide the container when the lid is in the closed position alower MVTR than the second seal would provide without the first seal.

In an exemplary embodiment of the present invention, the container isused for storing diagnostic test strips.

In an exemplary embodiment of the present invention, at least one of thethermoplastic-to-thermoplastic sealing surfaces is on aradially-projecting rim along an outside of the body.

In an exemplary embodiment of the present invention, the elastomer has aShore A hardness from 20 to 50, preferably from 20 to 40, morepreferably from 20 to 35. A skilled person in the art of injectionmolding would typically avoid using TPE materials with less than 50shore A hardness for container seals. This is because such soft TPEmaterials are generally difficult to adhere to the base polymer withoutdamaging or displacing the seal during molding. However, through moldingtechniques that Applicants developed, use of TPE materials with ahardness of less than 50 shore A for a container seal is made possible.Use of such low durometer material creates lower resistance to flowduring molding, advantageously creates lower resistance to flow duringmolding, enabling a thinner cross section. It is less prone to creatingknit lines in the finished seal that could adversely impact sealintegrity. In addition, the softer TPE material requires lesscompression force to seal, which reduces the likelihood of excessivevertical spring force, which could otherwise result in inadvertentopening of the container as discussed above.

In the design of a flip top container the cap opening force is acritical to quality characteristic of the product. The acceptable rangeof opening force is 3 to 7 lbf (pound-force) when measured by affixingthe body of the vial standing on the vial base and then applying anupward force to the underside of the bill of the cap, parallel to theaxis of the vial at a constant speed of 500 mm/min at a controlledtemperature of 20+/−2° C., with a preferred range of 4 to 6 lbf. Asdiscussed above, a container that is too easy to open may openinadvertently and a container with an opening force above this range maybe too difficult for the user to open.

The resistance to opening under differential pressure can optionally bemeasured by placing a container which has been opened and closed in theambient environment into a sealed chamber and then reducing the externalpressure in the chamber over a period of 30 seconds to one minute tocreate a differential pressure between the interior of the container andthe external environment of at least 450 mBar, which is the maximumpressure differential a container should be exposed to during commercialair transportation.

In an exemplary embodiment of the present invention, the elastomer has athickness of from 0.5 mm to 1.25 mm and optionally an exposed width ofthe outside vial rim is from 0 mm to 2.5 mm.

A vial in accordance with an exemplary embodiment of the presentinvention may be recycled after use. The recycling references theprimary material and the chasing arrow corresponds to that recycleclass. The vial lid seal with thermoplastic elastomer is designed with alower mass of elastomer to still allow the container to bere-used/recycled along with the primary material designation.

An additional elastomer seal thus reduces the moisture vaportransmission rate through the vial container lid seal to allow lessrequired desiccant mass. A combination of seals working in seriesenables reduced moisture vapor transmission, in combination with low lidopening and closing force to optimize the consumer experience. A lowmass of elastomer within the vial lid seal to allow vialre-use/recyclability of the vial's primary material.

It is noted that while exemplary embodiments are shown as roundcontainers with round seals, the invention is not limited thereto. It iscontemplated that the present invention can also be utilized in thecontext of non-round flip-top containers to improve seal integritybetween body and lid. In fact, it is contemplated that theelastomer-to-thermoplastic seals described herein would be particularlyuseful in enhancing seal integrity for non-round containers. Forexample, the first and second seals as disclosed herein may be utilizedin elliptical containers, square containers, rectangular containers,quadrilateral containers with rounded corners and many other shapes.Optionally, embodiments of the present invention are utilized withcontainer shapes and configurations disclosed in U.S. Pat. Pub. No.2011/0127269, which is incorporated by reference herein in its entirety.

It is further noted that the thermoplastic-to-thermoplastic seal (e.g.,the first seal 462) is not necessarily limited to the configuration asshown in the accompanying drawing figures. For example, in an optionalaspect, the thermoplastic-to-thermoplastic seal may be provided betweenan inner polymer ring depending from the underside of the lid base andinterfacing with a portion of the inner surface of the container bodywall. Optionally, in such an embodiment, an annular protrusion of theinner polymer ring engages a radial undercut within the inner surface ofthe container body wall to create a variation of the first seal 462disclosed with respect to FIGS. 6-10B. This variation of the first sealwould likewise require overcoming an opening force to disengage thatseal.

EXAMPLES

The invention will be illustrated in more detail with reference to thefollowing Examples, but it should be understood that the presentinvention is not deemed to be limited thereto.

Example 1

Tests were run to measure moisture ingress of 24 ml vials according tothe container embodiment shown in FIGS. 6-10B (Group A). Ambientconditions were set at 30° C. and 80% relative humidity. There were 48such containers in the tested population. These moisture ingress resultswere compared against testing data gathered from testing a population of7553 containers (Group B) that were identical in material respects tothe containers of Group A, except the containers of Group B onlyincluded the first seal (plastic-to-plastic)—not the second seal(elastomer-to-plastic). The following table shows a side-by-sidecomparison of the data collected.

Mean Ingress Standard Deviation Sample Group (μg/day) (μg/day) Size A399.8 22.61 48 B 440.9 105.5 7553

As the data show, the addition of the second seal resulted in ameaningful reduction of the mean ingress and a surprisingly significantreduction in the standard deviation of moisture ingress. Thissignificant reduction in standard deviation is notable and importantfrom a production standpoint. Essentially, the second seal incombination with the first seal allows for a much more controlled andpredictable (i.e., lower variation) in moisture ingress so thatcontainer moisture budgets can be much more precisely met. This allowsfor a reduction in desiccant material necessary per vial and hence areduction in production costs associated with the reduced amount ofdesiccant material.

Example 2

Tests were run to measure moisture ingress of 17 ml vials according tothe container embodiment shown in FIGS. 6-10B (Group A′). Ambientconditions were set at 30° C. and 70% relative humidity. There were 144such containers in the tested population. These moisture ingress resultswere compared against testing data gathered from testing a population of2923 containers (Group B′) that were identical in material respects tothe containers of Group A′, except the containers of Sample B′ onlyincluded the first seal (plastic-to-plastic)—not the second seal(elastomer-to-plastic). The following table shows a side-by-sidecomparison of the data collected.

Mean Ingress Standard Deviation Sample Sample (μg/day) (μg/day) Size A′305.4 20.54 144 B′ 420.7 76.91 2923

As with Example 1, the data show that addition of the second sealresulted in a meaningful reduction of the mean ingress and asurprisingly significant reduction in the standard deviation of moistureingress.

While the invention has been described in detail and with reference tospecific examples thereof, it will be apparent to one skilled in the artthat various changes and modifications can be made therein withoutdeparting from the spirit and scope thereof.

1-23. (canceled)
 24. A moisture tight container comprising: a bodydefining an interior configured for housing product, and an openingleading to the interior; a lid that is connected to the body by a hinge,the lid being movable with respect to the body between a closed positionin which the lid covers the opening and is mated to the body, and anopened position in which the lid is not mated to the body; a pluralityof seals between the body and the lid and in series when the lid is inthe closed position, the plurality of seals including at least a firstseal requiring an opening force to transition from the closed positionto the opened position, and a second seal in combination with the firstseal not requiring more than the opening force to transition from theclosed position to the opened position, the first seal being formed bymating incompressible thermoplastic-to-thermoplastic sealing surfaces,the first seal including an undercut of the body relative to a centralaxis of the body, the second seal being formed by matingelastomer-to-thermoplastic sealing surfaces, wherein theelastomer-to-thermoplastic sealing surfaces include an elastomer, thatis compressible and resilient, formed in the lid or on the body, whereina combination of the first and second seals in series reduces a moisturevapor ingress of the container while maintaining the opening force in arange that is ergonomically advantageous to a consumer, wherein theelastomer is injection molded with the body and lid in a multi-shotinjection molding process, wherein the opening force is from 3 to 7 lbf(pound-force).
 25. The container according to claim 24, wherein thecontainer when the lid is in the closed position has a moisture vaportransmission rate (MVTR) of less than 370 μg/day at 30° C. and 80% RH.26. The container of claim 25, wherein the elastomer is made from athermoplastic elastomer (TPE).
 27. The container of claim 26, wherein atleast one of the thermoplastic-to-thermoplastic sealing surfaces is on aradially-projecting rim along an outside of the body.
 28. The containerof claim 26, wherein at least one of the elastomer-to-thermoplasticsealing surfaces is on a radially-projecting rim along an outside of thebody.
 29. A moisture tight container comprising: a container body havinga base and a sidewall extending therefrom, the body defining an interiorconfigured for housing product, the sidewall terminates at a lip havinga top edge, the lip surrounds an opening leading to the interior; and alid movable with respect to the container body between a closed positionin which the lid covers the opening to create a moisture tight seal withthe body and an open position in which the opening is exposed, themoisture tight seal comprising a plurality of seals between the body andthe lid when the lid is in the closed position, the plurality of sealsincluding at least a first seal and a second seal, the first seal beingformed by mating a thermoplastic sealing surface of the body to athermoplastic sealing surface of the lid, the second seal being formedby mating a thermoplastic sealing surface of the body with anelastomeric sealing surface of the lid, the elastomeric sealing surfacebeing an elastomeric ring made from a thermoplastic elastomer (TPE), afirst portion of the elastomeric ring being compressed by the top edgeof the lip when the lid is in the closed position, a second portion ofthe elastomeric ring maintaining an original, uncompressed shape whenthe lid is in the closed position.
 30. The container of claim 29,wherein the first seal requires an opening force to transition from theclosed position to the opened position and the second seal incombination with the first seal does not require more than the openingforce to transition from the closed position to the opened position. 31.The container of claim 30, wherein the opening force is from 3 to 7 lbf(pound-force).
 32. The container of claim 29, wherein the elastomericring is injection molded with the container body and lid in a multi-shotinjection molding process.
 33. The container of claim 29, wherein thefirst seal includes an undercut of the body relative to a central axisof the body.
 34. The container of claim 33, wherein the lid includes adepending skirt, and wherein the undercut has a surface that mates witha corresponding surface of the skirt thereby forming the first seal. 35.The container of claim 29, wherein the elastomeric ring has a Shore Ahardness from 20 to 50 and a thickness from 0.25 mm to 1.25 mm.
 36. Thecontainer of claim 29, wherein the container, when the lid is in theclosed position, has a moisture vapor transmission rate (MVTR) of lessthan 400 μg/day at 30° C. and 80% RH.
 37. The container of claim 29,wherein the first seal and the second seal combined provide thecontainer when the lid is in the closed position a lower moisture vaportransmission rate (MVTR) than the first seal would provide without thesecond seal.
 38. The container of claim 29, further comprising aplurality of test strips stored therein.
 39. A moisture tight container,comprising: a body having a base and a sidewall extending upwardlytherefrom, the sidewall terminates at a lip opposite the base, the bodydefining an interior configured for housing product, the body furtherhaving an opening leading to the interior, the opening being surroundedby the lip, a rim projects radially outwardly from the sidewall 105below the opening; a lid having a base and a skirt depending therefrom,the lid being connected to the body by a living hinge, the hinge beingattached to the rim of the body, the lid being pivotable about the hingewith respect to the container body to move the container between aclosed position in which the lid covers the opening so as to create amoisture tight seal with the body and an open position in which theopening is exposed, the moisture tight seal comprising at least a firstseal and a second seal, wherein the first seal is formed by mating athermoplastic sealing surface of the body to a thermoplastic sealingsurface of the lid, the first seal is formed between an undercut of thebody relative to a central axis of the body and an undercut surface ofthe lid, the second seal being formed by mating a thermoplastic sealingsurface of the body with an elastomeric sealing surface of the lid, theelastomeric sealing surface comprising an elastomeric ring attached toan interior surface of the base of the lid, the elastomeric ring beingcompressed by an upper surface of the lip surrounding the opening whenthe lid is in the closed position, the elastomeric ring verticallycompressing when the lid is in the closed position.
 40. The container ofclaim 39, wherein vertical compression of the elastomeric ring causes aportion of the ring to elastically expand radially.
 41. The container ofclaim 40, wherein the portion of the ring elastically expands radiallyinto a void provided between the body and the lid.
 42. The container ofclaim 41, further comprising an elastomeric sealing surface attached toan interior surface of the lid base, wherein the moisture tight sealfurther includes a second elastomeric-to-thermoplastic seal created bymating the elastomeric sealing surface and a lip of the container body,the lip surrounding the opening of the container body.
 43. The containerof claim 39, wherein the container, when the lid is in the closedposition, has a moisture vapor transmission rate (MVTR) of less than 400μg/day at 30° C. and 80% RH, and wherein the elastomeric sealing surfacecomprises an elastomeric ring having a Shore A hardness from 20 to 50and a thickness from 0.25 mm to 1.25 mm.